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<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="https://unpkg.com/vue@next"></script>
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<body>
    <div id="app"></div>
</body>

<script>
    Vue.createApp({
        data(){
            return{
                counter:1
            }
        },
        // 钩子函数----页面加载完或渲染完就自动执行
        mounted(){
            // 计数器
            setInterval(()=>{
                // 从面向DOM编程，改为面向数据编程
                this.counter += 1

            },1000); //1000毫秒等于1秒
        },
        template: '<div>{{counter}}</div>'
    }).mount("#app")
</script>
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